1. Field of the Invention
The present invention relates to a liquid crystal display (LCD) and a method of manufacturing the same, and more particularly, to an LCD and a method of manufacturing the LCD which is capable of preventing electrical shorts between neighboring pixel electrodes.
2. Description of Background Art
A conventional LCD is driven by an active matrix method which employs thin film transistors (TFTs), signal lines, data lines and others for driving the pixels. Such a conventional LCD is widely used as a display device in audio-video (AV) and official-automation (OA) systems. The conventional LCD has a thinner thickness, a smaller size, a lighter weight, and a lower power consumption than other display devices, such as a cathode-ray-tube (CRT) device. Further, the conventional LCD has a good response speed and display quality for displaying moving video data.
FIG. 1 shows the structure of a conventional active matrix liquid crystal display (AMLCD) device.
As shown in FIG. 1, on a transparent insulation substrate (such as non-alkalic glass), a plurality of scan lines 10 extending in a horizontal direction and a plurality of data lines 20 extending in a vertical direction are formed. A pixel electrode 30 is formed in an area defined by two adjacent scan lines 10 and two adjacent data lines 20. A TFT 40 is electrically connected with the pixel electrode 30, the scan line 10, and the data line 20. The pixel electrode 30 overlaps a portion of the scan line 10. An insulating layer is formed between the pixel electrode 30 and scan line 10. The overlapping portion of the pixel electrode 30 and the overlapped portion of the scan line 10 function as the electrodes of a storage capacitor 70.
FIG. 2 shows a section of a storage capacitor and pixel electrodes in the conventional LCD.
As shown in FIG. 2, a metal segment 50 is formed on a gate insulation layer (not shown) covering the scan line 10. The metal segment 50 covers a portion of the scan line 10, whereas a protection layer (not shown) covers the metal segment 50. The metal segment 50 is electrically connected with the pixel electrode 30 through a storage contact hole 60 which exposes a surface of the metal segment 50. The overlapping portion of the pixel electrode 30, the metal segment 50 and the overlapped portion of the scan line 10 function as the electrodes of the storage capacitor 70.
FIG. 3 shows a cross-sectional view of FIG. 2, taken along line III-III.
As shown in FIG. 3, a scan line 10 made with an aluminum (Al) or chromium (Cr) metal is formed on a transparent insulation substrate 1. A gate insulation layer 11 including silicon oxide or silicon nitride covers the entire surface of the substrate 1. On the gate insulation layer 11, a metal segment 50 having Al or Cr is formed. A protective insulating layer (passivation layer) 17 having silicon nitride covers the metal segment 50. A storage contact hole 60 is formed through the passivation layer 17 for exposing a surface of the metal segment 50. On the passivation layer 17, a pixel electrode 30 having ITO (Indium Tin Oxide) is formed. The pixel electrode 30 is electrically connected with the metal segment 50 through the storage contact hole 60.
In the conventional LCD, however, the neighboring pixel electrodes are positioned to close to each other because each pixel electrode overlaps a substantial portion of the scan line. The overlapping portion of the pixel electrode is positioned too close to the neighboring pixel electrode. When the storage capacitor is not formed or is formed by another method, the distance between the neighboring pixel electrodes is 6 .mu.m which is greater than the width of the scan line (30 .mu.m).
Because the neighboring pixel electrodes are positioned so close to each other, when the data signal driven by the TFT is applied to one of the pixel electrodes, the neighboring pixel can be inadvertently driven, causing the pixel electrodes to be shorted out. When the pixel electrode short occurs, the display has point defects and poor color quality.